Harvard Gazette reported that participating in an eight-week
mindfulness meditation program appears to make measurable changes in
brain regions associated with memory, sense of self, empathy, and
stress. In a study published in Psychiatry Research: Neuroimaging, a team led by Harvard-affiliated researchers at Massachusetts General Hospital reported the results of their study, the first to document meditation-produced changes over time in the brain’s gray matter.
Sara Lazar, a Harvard Medical School instructor in psychology says although the practice of meditation is associated with a sense of
peacefulness and physical relaxation, practitioners have long claimed
that meditation also provides cognitive and psychological benefits that
persist throughout the day. This study demonstrates that changes in brain structure may underlie
some of these reported improvements and that people are not just feeling
better because they are spending time relaxing.
Previous studies from Lazar’s group and others found structural
differences between the brains of experienced meditation practitioners
and individuals with no history of meditation, observing thickening of
the cerebral cortex in areas associated with attention and emotional
integration. But those investigations could not document that those
differences were actually produced by meditation.
For the current study, magnetic resonance (MR) images were taken of the
brain structure of 16 study participants two weeks before and after they
took part in the eight-week Mindfulness-Based Stress Reduction (MBSR) at the University of Massachusetts Center for Mindfulness. In addition to weekly meetings that included practice of mindfulness
meditation — which focuses on nonjudgmental awareness of sensations,
feelings, and state of mind — participants received audio recordings for
guided meditation practice and were asked to keep track of how much
time they practiced each day. A set of MR brain images was also taken of
a control group of nonmeditators over a similar time interval.
The analysis of MR images, which focused on areas where
meditation-associated differences were seen in earlier studies, found
increased gray-matter density in the hippocampus, known to be important
for learning and memory, and in structures associated with
self-awareness, compassion, and introspection.
Participant-reported reductions in stress also were correlated with
decreased gray-matter density in the amygdala, which is known to play an
important role in anxiety and stress. Although no change was seen in a
self-awareness-associated structure called the insula, which had been
identified in earlier studies, the authors suggest that longer-term
meditation practice might be needed to produce changes in that area.
None of these changes were seen in the control group, indicating that
they had not resulted merely from the passage of time.
Britta Holzel, first author of the paper says it is fascinating to see the brain’s plasticity and that, by practicing
meditation, we can play an active role in changing the brain and can
increase our well-being and quality of life. Moreover, Amishi Jha, a University of Miami neuroscientist who investigates mindfulness-training’s effects on
individuals in high-stress situations, says these results shed light
on the mechanisms of action of mindfulness-based training. They
demonstrate that the first-person experience of stress can not only be
reduced with an eight-week mindfulness training program but that this
experiential change corresponds with structural changes in the amygdala,
a finding that opens doors to many possibilities for further research
on MBSR’s potential to protect against stress-related disorders, such as
post-traumatic stress disorder.
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